5 replies to this topic

[Simon151191]

Hi all, new member here as i just bought my first suby last week. Its a 2004 impreza rx so 2 litres of n/a goodness . When i bought it i was told it had a slight overheating problem but for the price and with some mechanical knowledge i thought it should be fine. On the way home (about 15kms) i had to pull over twice as it got hot and spat coolant out of the overflow bottle when stopped/moving slowly in traffic so when i got home, i let it cool down and pulled it to pieces which is where things got a little interesting. The bloke i bought it off assured me the thermostat had been replaced and there had been tests done for exhaust fumes in the coolant and compression tests a month ago, however when i drained the coolant, it was no more than slightly red and gunky water with tiny silvery floaties (chemy weld?). I pulled the thermostat and dropped it into boiling water and it opened but thought it best to replace it anyway along with the radiator and cap due to poor flow and staining at the bottom tank. Of course with that came a massive flush of the engine. Filled it back up and bled it as best i could without a funnel. Just warming it up in my driveway the bottom hose was still staying cold and the radiator was only luke-warm but i read that these need to be driven properly to get the bottom hose warm so decided to take it for a drive today (about 10km) and it started getting warm again, But it was no longer over filling the overflow bottle. Is it possible that there is an airlock or do you guys think there is something a little more sinister going on? Im thinking maybe water pump, which would explain the floaties, or dreading head gaskets. Let me know what you guys think, any help is very much appreciated! Thank you for your time

[El_Freddo]

Welcome to the forum!

How many km's on it for starters?

The issue could be a number of things. To me it points to head gaskets. That floating metal may have been a type of chemiweld or copper seal.

If it's a water pump issue it'll be leaking. Also ensure you install the thermostat "upside down" compared with traditional thermostat setups. Also always use a genuine thermostat - much more reliable and has a much larger opening than the after market units.

If going to do the HGs, it's a good idea to do some other general maintenance - it may add cost to the work but for peace of mind it's a very good investment. I would recommend:
- front and rear crank oil seals, and cam seals
- new water pump and cam belt kit, not just the belt, do the tensioner's as well
- coolant crossover pipe O rings on the top of the engine block
- any heater or rad hoses
- you might consider putting in a new clutch plate while the engine is out

If you do this you'll know the engine is good and won't be chasing issues that mean more downtime on the new ride that you no doubt just want to be driving.

For parts check out partsouq.com - you'll need your vin to search for parts Top site but be warned it can be dangerous too!

To bleed the cooling system I always have the car on ramps and some sort of bottle arrangement taped onto the radiator filler. Top up as much as possible without the engine running. Then start the engine and top it up as air leaves the system. Once this settles I let the engine warm up and cycle through two or three Thermo fan operations before shutting down the engine (coolant may come back up/fill the bottle filler on the radiator fill neck). Let cool, coolant will subside. Top up the overflow bottle with coolant. Replace the radiator cap and go for a decent drive that has a good period of time at cruising speed. Monitor temp gauge.

After the drive, check the overflow bottle coolant level , top up if necessary. Let car cool down, over night is best. Before next drive top up coolant in the radiator if needed and for the overflow bottle. Do this last procedure another two times if coolant was low/needed a top up

It's a process but it's worked for me each time.

Thinking about it, the other issue could be a blocked heater core. Back flush this and see if there's any change in operating temp. This circuit is the one responsible for regulating the thermostat opening...

Cheers

Bennie

[Liberty]

Welcome to SubyClub mate.

[Simon151191]

Thank you for your swift reply!

The car has 200,000kms on it.

Can i ask why you think its pointing to HGs? Not doibting you, just wondering which symptoms point that way? Im probably in denial about it, because i really dont want it to be that haha. Does the engine absolutely need to come out to do heads? Just because id be doing it on my front lawn with no engine crane, so if i can do it in place, even if its more effort, that might have to be the go.

With the thermostat, i admit, i did buy an aftermarket unit only because my work hours and locations makes it impossible for me to visit thr dealer. I installed it with the spring side to the engine, is that what you mean by upside down?

That site you recommended, ehy do you say its dangerous? Because i might spend all my pennies there or something else? Haha.

If this rain buggers off, ill flush the heater core and see what comes out of it and then bleed the system the way you’ve recommended today and see what happens and let you know! Fingers crossed its not too bad as i bought this car to drive to and from work so my wife can have her car back for the kids haha.

Cheers,

Simon

[El_Freddo]

200k km should be ok with proper maintenance.

Thermostat: that's correct

Partsouq.com - dangerous as in bits cheap that add up quick.

Thinking heads with the info you've given as a change of radiator hasn't done much. EJs can develop slight HG weaning that can go undetected for ages. His can then leak to a major failure at some point. That and how trustworthy was the previous owner? When ever someone tells me it's been tested or done I'm usually suspicious and will double check/make an effort to monitor after purchase - but that's just me.

When you say "still ran hot" after the radiator change, where on the gauge was the needle? Halfway is about normal.

If ending up having to do a head gasket change always do both as a set! It is easier with the engine out of the vehicle to do the HGs. I believe you can't remove the bolts from the head if you do it this way, which means you must have all the bolts in the head before you start fitting it again. Other tasks like cam belt fitment are loads easier out of the car rather than in it.

I'm hoping it's not a head gasket for your sake (and your wallet's!). Try that heater core flush, swap in a genuine thermostat at the same time then give it a good bleed and see where it's at from there.

Cheers

Bennie

[surge]

Sounds like head gaskets for sure. Yes it's easy to be in denial about it but you and up wasting time and money if you can't just accept it and move on.

Can do the head gaskets with engine in the car, but the issue is that you may need not only the heads resurfaced but also the deck of the block. Which is impossible to do when it's in the car...

Would almost be easier to find a non blown ej20 long block and swap it over. I'm sure you can find one for sale under $1000 if you look around.